Most continuous pan crystallizers are divided into a number of compartments in an attempt to promote plug-rate flow through the system. It is important that the system flow approach the plug rate of flow as closely as possible, so that crystal residence times in the continuous pan are uniform, leading to equal growth on all crystals and a uniform crystal size in the product massecuite leaving the pan.
One of the objects of the present invention is to provide a system for massecuite to pass from one compartment to another in such a way as to eliminate problems experienced with other types of continuous pans, such as:
(a) short-circuiting or by-passing of massecuite from one compartment to another.
(b) elimination of encrustation in the opening between compartments.
In order to overcome the latter problem, steam blowers needed to be installed in some pans at the cross-over ports, to prevent encrustation in the ports. This is expensive and detrimental to thermal economy.
Another object of the invention is to eliminate encrustation of sugar on baffles and other surfaces inside the pan. Such encrustation can lead to the formation of lumps or the dislodging of large pieces of encrustation which can block heating tubes or massecuite outlets.
A further object is to provide a condenser integral with the pan to reduce the cost of the continuous vacuum pan system.